Process of making dihydroxy carbon compounds



alpha-glycols.

late'rited Aug. 3, 1926. U V I UNITED STATES PATENT OFFICE.

' HARRY ESSEX AND ALGEB L. WARD, OI WILMINGTON, DELAWARE, ABSIGHOBS TOI. I.

DU PORT DE NEMOURS 6t COMPANY, OF WILHIHGTON, DELAWARE, A CORPORA- TJIONor nnmwum.

PROCESS OI MAKING IDIHYDROZY CARBON COMPOUNDS.

Il'o Drawing.

This invention relates to the production of dihydroxy compounds(alpha-glycols) from organic compounds containing at least one pair ofcarbon atoms united by a double bond. In'general our invention comprisesconverting an unsaturated organic compound into a halohydrin in such a.way that the resulting reaction mixture contains water and analkali-forming metal carbonate such as sodium or calcium carbonate inaddition to said halohydrin, and then heating said reaction mixture tobring about hydrolysis of the halohydrin.

In an investigation to find processes most suitable for the commercialsynthesis ofglycerol we discovered that allyl chloride couldbeconverted, with good yields, into glycerol dichlorhydrins by slowlypassing carbon dioxide into a mixture'of allyl chloride and a watersolution of an. alkali, or alkaline earth, metal hypochlorite, and thatthe resulting reaction mixture was so constituted that conversion of thedichlorhydrins into glycerol could be readily effected simply by heatingthe mixture, preferably with the addition of a further quantity ofcarbonate. This process is described and claimed in our Patent No.1,477,113, dated December 11, 1923.

We have now found that other carbon compounds containing an ethyleniclinkage may be converted in an analogous manner first into thecorresponding halohydrins, and then by hydrolysis, and without isolationof the halohydrins, into the corresponding The compounds which may becaused to undergo the above described transformation vary widely inmolecular structure and in chemical and physical properties, but theyare all characterized by pos sessing a pair of doubly'linked carbonatoms so situated with respect to the rest of the molecule as to becapable of combining additively with the OH and Cl radicals ofhypochlorous acid to form chlorhydrins. Examples of such compounds are(1) olefines, such as ethylene, propylene, butylene,'etc.; (2)aryl-substituted alkylenes, such as styrole (phenylethylene orvinylbenzene) and (3) substituted olefines with miscellaneoussubstituents, such as gamma-hydroxypropylene' (allyl alcohol).

Application filed November as, 1019. Serial No. 840,073.

Our new following examples process may be illustrated by the this method482 cu. ft. of ethylene and 241 cu. ft. of carbon dioxide, measured atstandard oondltions, are passed into a cold 5% hypochlorite solutioncontaining 100 lbs. of

sodium hy ochlorite. The ethylene'should preferably e admitted to thesolution in the form of very fine bubbles, which may be accomplished byforcing the ethylene throu h the ores of unglazed earthenware. esolutlon should be kept cold throughout the operation and the carbondioxide admitted sufliciently slowly to keep low the concentration offree hypochlorous acid. The resulting solution of-ethylene chlorhydrinis then heated to boiling under a reflux condenser and kept at thistemperature for several hours. If a test shows that chlorates areabsent, the ethylene glycol formed may be recovered by concentration anddistillation. The reactions involved are:

II. Phenyl glycol.

104 lbs. of styrole are added to'74.5 lbs. of sodium hypochlorite inwater solution,

the mixture vigorously stirred and carbon then hydrolyzed to phenylglycol by boiling the productunder a reflux condenser. The reatlonsinvolved are:

2C H .OH=GH,+2NaOO1+GO,+H,O=

2C,H,CHOH.OH Ol+Na CO 2G H GHOH.CH Cl+Na,CO,-| H,O=

2C, H,CHOH.GH,OH+2NaOl+C0,. I II Gig caring from allyl alcohol. 58 lbs.-of allyl alcohol are added to 74.5 lbs. of-sodium h chlorite in watersolu tion, the mixture vlgorously stirred and carbon dioxide passed intothe cooled solution so from cinnamic acid common on, 2Na001 00 2CH,OH.OHOH.CH,OH 2NaCl 00,. As evidence of the wide applicability of thisrocess there may be mentioned the production, in a manner similar tothat described. in the preceding examples, of phenylglyceric acid 1o,H,-.oHoH.oHoH.ooom

0.11.01 1; oHcooH of dih droxystearic acid from oleic acid, and oftrihydroxystearic acid from ncmole c 26' acid.

Various changes may be made in the process set forth in detail abovewithout departing from our invention. Thus in place of thealkali-forming metal 'hypochlonte referred to above, there may be usedother hypohalites such as sodium, calcium or barium hypobromite; theresulting haiohydrins are then hydrol zed to dihydroxyv comunds byheating t e reaction mixture as escribed in the specific examples.

We claim 1. The process of roducing a dihydroxy carbon compound w ichcomprises causin a carbon compound containing a pair 0 doubly linkedcarbon atoms to combine with hypohalous acid in the presence of analkaliforming metal carbonate to form a halohydrin, and heating thereaction mixture containing an alkali-forming metal carbonate to hydroze the halohydrin.

2. e process of producing phenylglycol which comprises passing carbondioxide mto a mixture of styrole and a water solution of sodiumhypochlorite, while keeping the mixture 0001, until substantially allthe h pochlorite has been decomposed, and then boiling the resultingmixture until the chlorhydrm contained therein is hydrolyzed to phenylglycol.

In testimony whereof-we afiix our signatures. Y

HARRY ESSEX. ALGER L. WARD.

